QUETTA, Pakistan — A bomb hidden in a water tank ripped through a crowded bazaar yesterday, killing at least 79 people and wounding 180, officials said.

Many of those wounded in the explosion in the city of Quetta remain in critical condition. The blast, which police said targeted the country’s minority Shiite Muslim sect, left numerous victims buried under rubble.

It was the deadliest incident since bombings in the same city killed 86 people last month, leading to days of protests that ended up toppling the local government.